Laser systems often include a laser device and one or more optical devices for manipulating the beam of coherent electromagnetic radiation emitted by the laser device. For example, laser systems may include optical devices such as lenses, windows, mirrors, prisms, wave plates, beam splitters, etc. These optical devices may be fabricated from glass materials such as, for example, silica (SiO2) glass or borosilicate glass.
Laser systems that employ large, high-powered lasers may require the use of relatively large optical devices to manipulate the beam of electromagnetic radiation emitted by the lasers. Optical devices generally must be at least substantially homogeneous and relatively free of defects. The probability that an optical device will not meet required specifications (e.g., specifications relating to homogeneity and the presence of defects) upon fabrication thereof increases exponentially with the size of the optical device. As a result, the cost of optical devices also increases exponentially with size. Presently, one of the major costs in laser systems is the cost of the optical devices used to manipulate the beam of electromagnetic radiation emitted by the lasers.
It has been observed that optical devices in laser systems, after a period of use, may begin to exhibit damage that degrades the performance of the optical devices until they are no longer suitable for use. In essence, an optical device may have a limited useable lifetime that is at least partially a function of the radiation dose to which the optical device is subjected by a laser.
In view of the above, there is a need in the art for optical devices that exhibit relatively longer useful lifetimes, and for methods of fabricating such optical devices for laser systems.